A little boy lost in unknown waters, a father's perilous journey to retrieve him — no, it's not "Finding Nemo." In this case, we're talking about 2011's best horror film to date, arriving July 12 on DVD and Blu-ray.

"Insidious"(Sony Pictures Home Entertainment, rated PG-13, DVD $30.99; Blu-ray Disc $35.99) is so smoothly told within the familiar bounds of the horror genre that many viewers may dismiss its germ of originality. There is no major new scream icon introduced, a la Freddie Kreuger or Pinhead, though there are certainly enough on-screen demons floating around to populate a haunted hayride or two.

No, what is original about it is its explanations for the unexplainable. Those wishing to peruse the menu of "Insidious" entrees for themselves should skip to the next section. What follows could be considered a spoiler or a teaser, depending on your need to know before wading too far in.

We've all heard the reports from near-death survivors of floating out of their body and hovering over the scene of an accident or an operating table. The term for this is astral projection, and it is considered both a spiritual skill and a special gift by mystics and shamans the world over.

In "Insidious," it has become a curse, passed along in the genes from one generation to the next. And so when all scientific rationales lead nowhere, two young parents are left to consider that their comatose son may indeed have left his body and gotten lost in a haunted twilight netherworld dubbed "The Further."

With the aid of a spiritualist and her team of young techno-nerds, the plan is hatched to penetrate The Further and bring the spirit of the lost boy back to his birthright world.

Getting there is a lot of fun for horror fans. There are haunted house shocks and demon-possession thrills, but "Saw" screenwriter Leigh Whannell doesn't allow it to stray into the buzz-kill realm of R-rated obscenity, torture or blasphemy.

The film was directed by James Wan and produced by the team behind "Paranormal Activity," but Whannell is the golden boy here. He offered a well-developed script with the first credible depiction of supernatural suburban peril since "Poltergeist." It uses some of the cinema verite techniques as "Paranormal Activity," but it also brings a lot more professional movie-making skills to the project.

"Insidious" looks and sounds quite impressive at home, especially with the enhanced presence of DTS-HD sound on the Blu-ray. Both editions have supplements on the making of the film, the creation of the various ghouls and specters and the challenges of laboring in the overworked haunted house genre.

More summer chills

Summer is the perfect time to kick back in your air-conditioned den and raise a little gooseflesh. So here's a quick look at some other new thrillers to watch out for, more or less in order of their effectiveness.

• "The Reef" (Image Entertainment, rated R, DVD $27.97; Blu-ray Disc $29.97). "Jaws" fanciers, get ready for a new feeding frenzy when this Great Barrier Reef thriller sails into stores July 19. Four Aussie yuppies and their captain set out for a three-hour tour — no, make that a sensual getaway to an uncharted stretch of islands. But when an unseen patch of coral rips through their hull and leaves them sinking into the sunset, the choice becomes death by increments or possible safety after a 12-mile swim through shark-infested waters. You will ask yourself what you would do in like situation — and you will be horrified by watching your options played out. The fact that the movie is beautifully shot and acted adds to its pulse-pounding intensity. It's extra yummy on Blu-ray, and comes with a "making of" featurette that only touches on the real-life news account that inspired the screenplay.

• "Fall Down Dead"(Image Entertainment, rated R, DVD $27.97). The great Udo Keir makes for a particularly creepy serial killer on the prowl in the big city over the course of one long Christmas Eve. Dominique Swain plays the damsel in distress who has the misfortune of witnessing the latest slashing by the so-called Picasso Killer. None of it makes much logical sense, but it has some shocks and it has been patiently waiting for distribution since 2007. Look for the late and always-aloof David Carradine as a security guard in one of his final film roles.

• "Dinocroc vs. Supergator"(Anchor Bay Entertainment, not rated, DVD $19.98; Blu-ray Disc $24.99). And watch for the late David Carradine in another of his final roles in this SyFy Channel original movie from the Roger Corman grindhouse. If you have a high tolerance for cheesy acting, crayon-penned dialogue and truly atrocious CGI monsters, this one's for you. Guess what has escaped from a shady biotech lab with an insatiable hunger for women in bikinis and hot tubs? Not fair, you looked!

• "Season of the Witch"(20th Century-Fox Home Entertainment, rated PG-13, DVD $29.98; Blu-ray Disc $39.99). Nicolas Cage alert! Yes, the hardest working hack in Hollywood is back with his haunted, what-am-I-doing-here eyes and his oh-yeah-the-paycheck lips. This time, the dubious supernatural hijinks get a period spin as Cage and a fellow warrior-knight (Ron Perlman) wake up after 10 years of sacking Medieval villages to realize they may have caused a bit of collateral damage along the way. You think? They repent by agreeing to deliver an accused witch to a remote monastery, suffering from bad karma all the way. I don't know which is worse here, the ludicrous dialogue or the rabid anti-Christian bigotry.

• "The Warrior's Way"(20th Century-Fox Home Entertainment, rated R, DVD $29.98; Blu-ray Disc $39.99). After a lifetime spent proving his martial arts prowess as a warrior-assassin, famed swordsman Jang Dong Gun wakes up to realize he may have caused some collateral damage along the way. He repents and ends up in America's Old West, somehow erected on sound stages. This is an oddball exercise in shaping a heroic folk fable via the blatant artificiality of tarted-up lighting designs and CGI stunts. Despite all the action, a real dramatic conflict is a long time developing, and involves Danny Huston as the meanest villain since the heyday of the Saturday matinee. Poor Geoffrey Rush makes an ignoble career fall from the high of "The King's Speech" to being forced here to play a stock town drunk.

• "Passion Play"(Image Entertainment, rated R, DVD $27.97; Blu-ray Disc $29.97).Mickey Rourke alert! In a universe where Mickey Rourke is a movie star, anything can happen. So maybe you won't have any trouble suspending your disbelief when Rourke runs across a real-life angel — with large feathered wings and all — and lives to regret his decision to sell her to a melancholic mob boss (played, also unbelievably, by Bill Murray).